There is growing acceptance of techniques that leverage networked connectivity for extending the resources of host computer systems. In particular, networked connectivity is being widely utilized for specialized applications such as attaching storage to computers. iSCSI makes use of TCP/IP as a transport for the SCSI parallel bus to enable low cost remote centralization of storage. The problem with iSCSI is it has a relatively narrow (storage) focus and capability.
PCI Express, as the successor to PCI bus, has moved to the forefront as the predominant local host bus for computer system motherboard architectures. A cabled version of PCI Express allows for high performance directly attached bus expansion via docks or expansion chassis. These docks and expansion chassis may be populated with any of the myriad of widely available PCI Express or PCI/PCI-X bus adapter cards. The adapter cards may be storage oriented (i.e. Fibre Channel, SCSI), video processing, audio processing, or any number of application specific Input/Output (I/O) functions. A limitation of PCI Express is that it is limited to direct attach expansion.
A hardware/software system and method that collectively enables virtualization of the host bus computer's native I/O system architecture via the Internet, LANs, WANs, and WPANs is described in commonly assigned U.S. patent application Ser. No. 12/148,712, now U.S. Pat. No. 7,734,859. The system described, designated “i-PCI”, achieves technical advantages as a system and method that collectively enables virtualization of the host computer's native I/O system architecture via the Internet, LANs, WANs, and WPANs. The system includes a solution to the problems of the relatively narrow focus of iSCSI, the direct connect limitation of PCI Express.
The i-PCI solution allows devices native to the host computer native I/O system architecture—including bridges, I/O controllers, and a large variety of general purpose and specialty I/O cards—to be located remotely from the host computer, yet appear to the host system and host system software as native system memory or I/O address mapped resources. The end result is a host computer system with unprecedented reach and flexibility through utilization of LANs, WANs, WPANs and the Internet.
Referring to FIG. 1, the i-PCI solution is a hardware, software, and firmware architecture that collectively enables virtualization of host memory-mapped I/O systems. The i-PCI protocol extends the PCI I/O System via encapsulation of PCI Express packets within network routing and transport layers and Ethernet packets and then utilizes the network as a transport.
For extended systems there is a general desire to eliminate the use of cables if possible. Typically, cable elimination is mentioned for those applications where mobility is required, cabling is judged unsightly, or simplified interconnection is desired. Commonly assign U.S. patent application Ser. No. 12/148,712 disclosed a wireless implementation for computer expansion and I/O virtualization, the teachings which are incorporated by reference.
It is would be highly advantageous if wireless computer system expansion and I/O virtualization could employ ad hoc capability, such that the resources available via a wireless implementation could come and go in manner similar to the way that I/O resources are hot-plugged in a conventional computer system.